Surgical stapling apparatus

ABSTRACT

A loading unit for use with a surgical stapling apparatus is provided and includes a tool assembly having a cartridge assembly and an anvil assembly that are movable in relation to one another; a surgical buttress releasably secured to a tissue contacting surface of the anvil assembly and/or the cartridge assembly, wherein each surgical buttress is secured to the anvil assembly and/or the cartridge assembly by at least one anchor; a release assembly associated with the anvil assembly and/or the cartridge assembly; and a drive assembly slidably translatable through the tool assembly between proximal and distal positions, wherein the drive assembly actuates the release assembly to thereby release the anchor to free the surgical buttress from the anvil assembly and/or the cartridge assembly.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 12/414,943 filed Mar. 31, 2009 now U.S. Pat. No. 8,011,550. This application is also a continuation in part of U.S. patent application Ser. No. 12/342,400 filed Dec. 23, 2008 now U.S. Pat. No. 8,011,555, which is a continuation in part of International Application No. PCT/US2008/002981, filed Mar. 5, 2008, which claims priority to and the benefit of U.S. Provisional Application No. 60/905,566 filed Mar. 6, 2007, and the disclosures of each of the above-identified applications are hereby incorporated herein by reference in their entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to a surgical apparatus having a buttress material incorporated therewith. More particularly, the present disclosure relates to a surgical stapling apparatus including a detachable surgical buttress and/or an endoscopic surgical stapling apparatus that includes a detachable surgical buttress.

2. Background of Related Art

Surgical devices for grasping or clamping tissue between opposing jaw structure and then joining tissue by surgical fasteners are well known in the art. In some instruments a knife is provided to cut the tissue which has been joined by the fasteners. The fasteners are typically in the form of surgical staples but two-part polymeric fasteners can also be utilized.

Instruments for this purpose can include two elongated jaw members which are respectively used to capture or clamp tissue. In certain surgical staplers, one of the jaw members carries a staple cartridge which houses a plurality of staples arranged in at least two lateral rows while the other jaw member has an anvil that defines a surface for forming the staple legs as the staples are driven from the staple cartridge. The stapling operation is effected by cam members that travel longitudinally through the staple cartridge, with the cam members acting upon staple pushers to sequentially eject the staples from the staple cartridge. A knife can travel between the staple rows to longitudinally cut and/or open the stapled tissue between the rows of staples. Such instruments are disclosed, for example, in U.S. Pat. No. 3,079,606 and U.S. Pat. No. 3,490,675.

Another stapler disclosed in U.S. Pat. No. 3,499,591 also applies a double row of staples on each side of the incision. This patent discloses a surgical stapler that has a disposable loading unit in which a cam member moves through an elongate guide path between two sets of staggered staple carrying grooves. Staple drive members are located within the grooves and are positioned in such a manner so as to be contacted by the longitudinally moving cam member to effect ejection of the staples from the staple cartridge of the disposable loading unit. Other examples of such staplers are disclosed in U.S. Pat. Nos. 4,429,695 and 5,065,929.

Each of the instruments described above is designed for use in surgical procedures in which surgeons have direct manual access to the operative site. However, in endoscopic or laparoscopic procedures, surgery is performed through a small incision or through a narrow cannula inserted through small entrance wounds in the skin. In order to address the specific needs of endoscopic and/or laparoscopic surgical procedures, endoscopic surgical stapling devices have been developed and are disclosed in, for example, U.S. Pat. No. 5,040,715 (Green, et al.); U.S. Pat. No. 5,307,976 (Olson, et al.); U.S. Pat. No. 5,312,023 (Green, et al.); U.S. Pat. No. 5,318,221 (Green, et al.); U.S. Pat. No. 5,326,013 (Green, et al.); U.S. Pat. No. 5,332,142 (Robinson, et al.); and U.S. Pat. No. 6,241,139 (Milliman et al.), the entire contents of each of which are hereby incorporated herein by reference.

Tyco Healthcare Group, LP, the assignee of the present application, has manufactured and marketed endoscopic stapling instruments, such as the Multifire ENDO GIA™. 30 and Multifire ENDO GIA™. 60 instruments, for a number of years. These instruments include a surgical stapling apparatus and a loading unit. Typically, the loading unit is attached to the apparatus immediately prior to surgery. After use, the loading unit can be removed from the apparatus and a new loading unit can be fastened to the apparatus to perform additional stapling and/or cutting operations. These instruments have provided significant clinical benefits. Nonetheless, improvements to these instruments are still desirable.

When stapling relatively thin or fragile tissues, it is important to effectively seal the staple line against air or fluid leakage. Additionally, it is often necessary to reinforce the staple line against the tissue to prevent tears in the tissue or pulling of the staples through the tissue. One method of preventing tears or pull through involves the placement of a biocompatible fabric reinforcing material, or “buttress” material, between the staple and the underlying tissue. In this method, a layer of buttress material is placed against the tissue and the tissue is stapled in conventional manner. In another method, the buttress material is positioned on the stapling instrument itself prior to stapling the tissue. An exemplary example of this is disclosed in U.S. Pat. No. 5,542,594 to McKean et al., the entire content of which is incorporated herein by reference. In McKean et al., a tube of buttress material is slipped over the jaw of the stapler. The stapler is then actuated to staple the subject tissue and secure the buttress material between the tissue and staple line to reinforce the tissue and staple line.

SUMMARY

In accordance with the present disclosure a surgical stapling apparatus is provided including a housing; a handle supported by the housing; an elongated body extending distally from the housing; and a tool assembly at the distal end of the elongated body. The tool assembly has a cartridge assembly including a cartridge having a plurality of surgical fasteners therein, and an anvil assembly, wherein at least one of the cartridge assembly and anvil assembly being movable in relation to the other of the cartridge assembly and anvil assembly, wherein the anvil assembly includes an anvil plate, and wherein each of the anvil plate and the staple cartridge define an elongate longitudinal slot. The surgical stapling apparatus further includes a surgical buttress releasably secured to a tissue contacting surface of at least one of the anvil plate and the staple cartridge, wherein each surgical buttress is secured to the at least one of the anvil assembly and the cartridge assembly by at least one anchor; a release assembly associated with the at least one of the anvil assembly and the cartridge assembly; and a drive assembly slidably translatable through the tool assembly from a proximal position to a distal position, wherein the drive assembly actuates the release assembly to thereby release the anchor and to free the surgical buttress from the at least one of the anvil assembly and cartridge assembly.

The release assembly may grip the at least one anchor prior to an actuation of the drive assembly.

The at least one of the anvil assembly and the cartridge assembly may define a side slot for receiving an end of the at least one anchor therein.

The release assembly may include a first bar extending across the longitudinal slot prior to an actuation of the drive assembly; and a second bar, connected to and actuatable by the first bar, having an end extending at least partially into the side slot, prior to an actuation of the drive assembly.

In use, as the drive assembly is advanced to the distal position, the drive assembly may actuate the first bar of the release assembly which in turn may actuate the second bar of the release assembly to release the anchor disposed within the side slot.

Each of the anvil assembly and the cartridge assembly may include a release assembly. Each of the anvil assembly and the cartridge assembly may define a side slot for receiving the anchor of each surgical buttress.

Each release assembly may include a first bar extending across the longitudinal slot prior to an actuation of the drive assembly; and a second bar, connected to and actuatable by the first bar, having an end extending at least partially into the side slot, prior to an actuation of the drive assembly. In use, as the drive assembly is advanced to the distal position, the drive assembly may actuate the first bar of each release assembly which in turn may actuate the second bar of each release assembly to release the anchor disposed within the each side slot.

At least one of the anvil assembly and the cartridge assembly may include a constricting, open-ended, side slot configured to grip an end of the anchor, and wherein the release assembly may push the end of the anchor out of the side slot, upon a distal advancement of the drive assembly.

The release assembly may include a pusher that is in operative association with the side slot retaining the end of the anchor. The pusher may be actuatable by a distally advancing drive member to push the end of the anchor out of the side slot.

The pusher of the release assembly may be one of pivotally connected to and slidably supported in at least one of the anvil assembly and the cartridge assembly.

The anchor may be a suture engaging the surgical buttress and the at least one of the cartridge assembly and the anvil assembly. The anchor may be an extension of the surgical buttress and engages the at least one of the cartridge assembly and the anvil assembly.

According to another aspect of the present application, a loading unit for use with a surgical stapling apparatus is provided and includes a tool assembly having a cartridge assembly including a cartridge having a plurality of surgical fasteners therein, and an anvil assembly, at least one of the cartridge assembly and the anvil assembly being movable in relation to the other of the cartridge assembly and anvil assembly, wherein the anvil assembly includes an anvil plate and, wherein each of the anvil plate and the staple cartridge define an elongate longitudinal slot; a surgical buttress releasably secured to a tissue contacting surface of at least one of the anvil plate and the staple cartridge, wherein each surgical buttress is secured to the at least one of the anvil assembly and the cartridge assembly by at least one anchor; a release assembly associated with the at least one of the anvil assembly and the cartridge assembly; and a drive assembly slidably translatable through the tool assembly from a proximal position to a distal position, the drive assembly actuating the release assembly to thereby release the anchor to free the surgical buttress from the at least one of the anvil assembly and cartridge assembly.

The release assembly may grip the at least one anchor prior to an actuation of the drive assembly.

At least one of the anvil assembly and the cartridge assembly may define a side slot for receiving an end of the at least one anchor therein.

The release assembly may include a first bar extending across the longitudinal slot prior to an actuation of the drive assembly; and a second bar, connected to and actuatable by the first bar, having an end extending at least partially into the side slot, prior to an actuation of the drive assembly.

In use, as the drive assembly is advanced to the distal position, drive assembly actuates the first bar of the release assembly which in turn actuates the second bar of the release assembly to release the grip on the end of the at least one anchor disposed within the side slot.

Each of the anvil assembly and the cartridge assembly may include a release assembly.

At least one of the anvil assembly and the cartridge assembly may include a constricting, open-ended, side slot configured to grip an end of the anchor disposed therein, and wherein the release assembly may push the end of the anchor out of the side slot, upon a distal advancement of the drive assembly.

Additional advantages will become apparent from the description which follows, taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will be further described with reference to the accompanying drawings, wherein like reference numerals refer to like parts in the several views, and wherein:

FIG. 1 is a perspective view of a surgical stapling apparatus according to an embodiment of the present disclosure;

FIG. 2 is a top, perspective view, with parts separated, of a distal end of a loading unit of the surgical stapling apparatus of FIG. 1;

FIG. 2A is an enlarged perspective view of a distal end of an anvil assembly of the loading unit illustrating a surgical anvil buttress operatively secured to a tissue contacting surface thereof;

FIG. 2B is an enlarged perspective view of a cartridge assembly of the loading unit illustrating a surgical cartridge buttress secured to a tissue contacting surface thereof;

FIG. 3 is a top, perspective view of a distal end of an anvil assembly of the loading unit including a suture release assembly according to an embodiment of the present disclosure, shown in an open configuration;

FIG. 4 is a top, perspective view of the anvil assembly of FIG. 3, illustrating the parts of the suture release assembly thereof separated;

FIG. 5 is a bottom, perspective view of the anvil assembly of FIGS. 3 and 4;

FIG. 6 is a top, plan view of the anvil assembly of FIGS. 3-5, illustrating the suture release assembly thereof in the closed configuration;

FIG. 7 is a top, plan view of the anvil assembly of FIG. 6, with a retainer removed therefrom;

FIG. 8 is a top, plan view of the anvil assembly of FIGS. 3-7, illustrating the suture release assembly thereof in the open configuration;

FIG. 9 is a top, plan view of the anvil assembly of FIG. 8, with a retainer removed therefrom;

FIG. 10 is a top, perspective view of a distal end of a cartridge assembly of the DLU including a suture release assembly according to an embodiment of the present disclosure;

FIG. 11 is a top, perspective view of the cartridge assembly of FIG. 10, illustrating the parts of the suture release assembly thereof separated;

FIG. 12 is a bottom, perspective view of a distal end of the cartridge assembly of FIGS. 10 and 11;

FIG. 13 is a top, plan view of the cartridge assembly of FIGS. 10-12, illustrating the suture release assembly thereof in the closed configuration;

FIG. 14 is a top, plan view of the cartridge assembly of FIGS. 10-13, illustrating the suture release assembly thereof in the open configuration;

FIG. 15 is a perspective view of a distal end of a loading unit including suture release assemblies according to another embodiment of the present disclosure;

FIG. 16 is an enlarged view of the indicated area of detail of FIG. 15;

FIG. 17 is a top, perspective view of a distal end of an anvil assembly (with an anvil cover removed), illustrating a suture release assembly thereof in an actuated configuration;

FIG. 18 is a top, perspective view of the distal end of the anvil assembly of FIG. 17, illustrating the parts of the suture release assembly thereof separated;

FIG. 19 is a top, plan view of the anvil assembly of FIGS. 17 and 18, illustrating the suture release assembly thereof in an unactuated configuration;

FIG. 20 is a top, plan view of the anvil assembly of FIGS. 17-19, illustrating the suture release assembly thereof in an actuated configuration;

FIG. 21 is a bottom, perspective view of a distal end of a cartridge assembly of the DLU of FIG. 15, illustrating a suture release assembly thereof separated therefrom;

FIG. 22 is a top, perspective view of the suture release assembly of FIG. 21;

FIG. 23 is a bottom, perspective view, with parts separated, of the suture release assembly of FIGS. 21 and 22;

FIG. 24 is a top, plan view of the suture release assembly of FIGS. 21-23, illustrating the suture release assembly thereof in an unactuated configuration;

FIG. 25 is a top, plan view of the suture release assembly of FIGS. 21-24, illustrating the suture release assembly thereof in an actuated configuration;

FIG. 26 is a top, plan view of a distal end of an anvil assembly of a loading unit including a suture release assembly according to yet another embodiment of the present disclosure;

FIG. 27 is a top, perspective view, with parts separated, of the distal end of the anvil assembly of FIG. 26;

FIG. 28 is a top, plan view of the distal end of the anvil assembly of FIGS. 26 and 27, illustrating the suture release assembly thereof in an unactuated configuration;

FIG. 29 is a top, plan view of the distal end of the anvil assembly of FIGS. 26-28, illustrating the suture release assembly thereof in an actuated configuration;

FIG. 30 is a top, plan view of a distal end of an anvil assembly of a loading unit including a suture release assembly according to still another embodiment of the present disclosure, illustrating the suture release assembly thereof in an unactuated configuration;

FIG. 31 is a top, plan view of the distal end of the anvil assembly of FIG. 30, illustrating the suture release assembly thereof in an actuated configuration;

FIG. 32 is a top, perspective view of a distal end of a cartridge assembly of a loading unit including a suture release assembly according to a further embodiment of the present disclosure;

FIG. 33 is a top, perspective view of the suture release assembly of FIG. 32;

FIG. 34 is a bottom, perspective view of the suture release assembly of FIGS. 32 and 33;

FIG. 35 is a bottom, perspective view, with parts separated, of the suture release assembly of FIGS. 32-34;

FIG. 36 is a top, perspective view, with parts separated, of the suture release assembly of FIGS. 32-35;

FIG. 37 is a top, plan view of the suture release assembly of FIGS. 32-36, illustrating the suture release assembly in an unactuated configuration; and

FIG. 38 is a top, plan view of the suture release assembly of FIGS. 32-37, illustrating the suture release assembly in an actuated configuration.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the presently disclosed surgical stapling apparatus and loading unit will now be described in detail with reference to the drawings, in which like reference numerals designate identical or corresponding elements in each of the several views.

In the drawings and in the description that follows, the term “proximal”, as is traditional, will refer to the end of the stapling apparatus which is closest to the operator, while the term “distal” will refer to the end of the apparatus which is furthest from the operator.

FIG. 1 shows a surgical apparatus, e.g., surgical stapling apparatus, generally referred to as 10. In the interest of brevity, this disclosure will focus primarily on to the tool assembly of the surgical stapling apparatus 10. A detailed discussion of the remaining components and method of use of surgical stapling apparatus 10 is disclosed in U.S. Pat. No. 6,241,139, the disclosure of which is hereby incorporated by reference herein.

Surgical stapling apparatus 10 is an endoscopic apparatus and includes a handle assembly 12 and an elongated body 14 extending from handle assembly 12. A loading unit 16 is releasably secured to the distal end of elongated body 14. Furthermore, the present disclosure contemplates surgical stapling apparatus that have a replaceable cartridge that is received in the jaws of the apparatus.

Loading unit 16 includes a tool assembly 17 having a cartridge assembly 18 housing a plurality of surgical fasteners or staples 84 (see FIG. 2) and an anvil assembly 20 secured in juxtaposed relation relative to cartridge assembly 18, wherein anvil assembly 20 and cartridge assembly 18 are moveable to or away from one another to close or open tool assembly 17. As shown herein, loading unit 16 is configured to apply six (6) linear rows of staples, in loading units measuring from about 30 mm to about 60 mm in length. Loading units for applying any number of rows of staples, having staple pockets arranged in various patterns and/or loading units and end effectors having any other lengths, e.g., 45 mm, are also envisioned. Handle assembly 12 includes a stationary handle member 22, a movable handle member 24, and a barrel portion 26.

A rotatable member 28 is mounted on the forward end of barrel portion 26 to facilitate rotation of elongated body 14 and attached loading unit 16 with respect to handle assembly 12. An articulation lever 30 is also mounted on the forward end of barrel portion 26 adjacent rotatable member 28 to facilitate articulation of tool assembly 17. Preferably, a pair of knobs 32 are movably positioned along barrel portion 26. Knobs 32 are advanced distally to approximate or close cartridge and/or anvil assembly 18, 20, and retracted proximally to unapproximate or open cartridge and/or anvil assembly 18, 20.

Loading unit 16 is desirably selectively removably couplable to elongated body 14. Loading unit 16 includes a housing portion 36 having a proximal end adapted to releasably engage the distal end of elongated body 14. A mounting assembly 38 is pivotally secured at “P” to the distal end of housing portion 36, and is configured to receive the proximal end of tool assembly 17 such that pivotal movement of tool assembly 17 about an axis at “P”, perpendicular to the longitudinal axis of housing portion 36, effects articulation of tool assembly 17.

With general reference to FIG. 2, loading unit 16 includes a mounting assembly 40. Mounting assembly 40 includes an upper and a lower mounting portion 40 a, 40 b, respectively. An axial drive assembly 50 is operatively associated with and slidably disposed between cartridge and/or anvil assembly 18, 20. With reference to FIG. 2, axial drive assembly 50 includes an elongated drive beam 52 having a distal end 54 and a proximal end 56. Drive beam 52 may be constructed from a single sheet of material or, preferably, multiple stacked sheets.

Proximal end 56 of drive beam 52 of drive assembly 50 includes a pair of resilient engagement fingers that receive a pusher. The pusher is dimensioned and configured to mountingly engage a drive member, e.g., a drive rod or control rod (not shown) when the proximal end of loading unit 16 is engaged with elongated body 14 of surgical stapling apparatus 10. The control rod functions to impart axial movement of drive assembly 50 from handle assembly 12.

Distal end 54 of drive beam 52 of drive assembly 50 includes a head 60 with a laterally extending upper portion 64 a, a laterally extending lower portion 64 b, and a central wall portion 62. A distal edge of central wall portion 62 defines a knife blade or the like 66.

As seen in FIG. 2, anvil assembly 20 includes an anvil plate 70 having a plurality of staple deforming pockets/cavities (not shown) and a cover plate 72 secured to a top surface of anvil plate 70, having a cavity (not shown) is defined therebetween. The cavity defined between the anvil plate 70 and cover plate 72 is dimensioned to receive the upper portion 64 a of head 60 therein. A longitudinal slot 70 b extends through anvil plate 70 to facilitate passage of central wall portion 62 of head 60 therethrough. Additionally, cover plate 72 defines a pair of opposed recesses 72 a formed therein which align with the proximal pair of recesses 70 d formed in anvil plate 70 when cover plate 72 is assembled with anvil plate 70.

With continued reference to FIG. 2, anvil plate 70 defines a proximal pair of recesses 70 d formed near a proximal end of anvil plate 70 and disposed, one each, on opposed sides of longitudinal slot 70 b. Anvil plate 70 defines a distal pair of recesses 70 e formed near a distal end of anvil plate 70 and disposed, one each, on opposed sides of longitudinal slot 70 b. In one embodiment, at least one of the recesses of each of the proximal pair of recesses 70 d and the distal pair of recesses 70 e is preferably non-circular and constricting, or has a reduced width dimension, so as to frictionally engage and/or pinch an anchor “S”.

As used herein the term anchor is understood to include and is not limited to sutures, threads, tethers, straps, bands, lines, wires, cables, fasteners, tacks or any other material suitable for the intended purpose disclosed herein. In certain embodiments, the anchor is an extension of the staple line reinforcement material discussed below. The anchor may comprise an integral part of the staple line reinforcement material, or may be formed from the same or a similar material and attached to the staple line reinforcement material.

As seen in FIGS. 2 and 2A, anvil assembly 20 further includes a surgical anvil buttress “B1”, pledget or the like operatively secured to a lower surface or tissue contacting surface of anvil plate 70, by an anchor “S”, to overlie at least some of anvil pockets 70 a and/or at least a portion of a length of longitudinal slot 70 b. In particular, an anchor “S” is wrapped over a proximal portion of surgical anvil buttress “B1” and cinched in each of the proximal pair of recesses 70 d and an anchor “S” is wrapped around a distal portion of the surgical anvil buttress “B1” and cinched in each of the distal pair of recesses 70 e.

Surgical anvil buttress “B1” includes a proximal pair of notches formed in side edges aligned with the proximal pair of recesses 70 d of anvil plate 70, a distal pair of notches formed in side edges thereof aligned with the distal pair of recesses 70 e of anvil plate 70, and a proximal notch formed in a proximal edge thereof aligned with longitudinal slot 70 b when surgical anvil buttress “B1” is secured to anvil assembly 20. Surgical anvil buttress “B1” further includes a tongue or tab extending from a distal edge thereof to facilitate with the attachment of surgical anvil buttress “B1” to anvil assembly 20 during the assembly process. It is contemplated that the tongue is removed from surgical anvil buttress “B1” following securement of surgical anvil buttress “B1” to anvil assembly 20 and prior to packaging or shipment.

As seen in FIGS. 2-9, anvil assembly 20 further includes a release assembly 74 disposed between anvil plate 70 and cover plate 72 at a location in operative registration with the distal pair of recesses 70 e. Release assembly 74 includes a guide plate 75 defining an arcuate slot 75 a formed therethrough. Slot 75 a is configured and dimensioned to receive a tool (not shown) therethrough. The function and purpose of slot 75 a will be discussed in greater detail below.

Release assembly 74 further includes a lock or anchor bar 76 pivotally connected to anvil plate 70 (as seen in FIGS. 4 and 5) and/or optionally cover plate 72 (shown in FIG. 2). Anchor bar 76 includes a body portion 76 a defining an elongate channel or slot 76 b therein and a finger 76 c extending from an edge thereof. Finger 76 c is in operative registration with one of the distal pair of recesses 70 e, preferably, the one of the distal pair of recesses having the relatively larger width dimension.

Suture release assembly 74 further includes an anchor bar actuation member 77 pivotally connected to anvil plate 70 (as seen in FIGS. 4 and 5) and/or optionally cover plate 72 (shown in FIG. 2). Actuation member 77 includes an eccentric cam 77 a defining a central axis of rotation about which actuation member is permitted to rotate. Actuation member 77 includes a nub or boss 77 b extending from a surface of eccentric cam 77 a in a direction substantially parallel to and offset a radial distance from the central axis of rotation of eccentric cam 77 a. Boss 77 b is slidably and rotatably disposed in elongate slot 76 b of anchor bar 76. Actuation member 77 further includes a release bar 77 c extending substantially tangentially from eccentric cam 77 a from a side substantially opposite to boss 77 b. Release bar 77 c defines a pin 77 d formed thereon which is in registration with the arcuate slot 75 a of guide plate 75. In operation, as eccentric cam 77 a is rotated, pin 77 d of release bar 77 c follows along the path of arcuate slot 75 a of guide plate 75.

As seen in FIGS. 6 and 7, suture release assembly 74 includes a locking or anchoring configuration wherein finger 76 c of anchor bar 76 extends into or overlies the respective one of the pair of distal recesses 70 e in operative registration therewith, release bar 77 c of actuation member 77 extends across knife slot 70 b of anvil plate 70, and pin 77 d of release bar 77 c is disposed at or near a first end of arcuate slot 75 a of guide plate 75. It is contemplated that suture release assembly 74 may include a friction fit or snap fit feature for maintaining and/or retaining suture release assembly 74 in the locking or anchoring configuration at all times following the manufacturing/assembly process and prior to a complete firing of surgical stapling apparatus 10.

As seen in FIGS. 8 and 9, suture release assembly 74 includes an open or release configuration wherein finger 76 c of anchor bar 76 does not extend into or overlie the respective one of the pair of distal recesses 70 e in operative registration therewith, release bar 77 c of actuation member 77 does not extend across knife slot 70 b of anvil plate 70, and pin 77 d of release bar 77 c is disposed at or near a second end of arcuate slot 75 a of guide plate 75.

Suture release assembly 74 is used by a manufacturer during the assembly process of surgical stapling apparatus 10 to secure, with a surgical suture or tether, a surgical anvil buttress “B” to a tissue contacting surface of the anvil plate 70, and by the end user of surgical stapling apparatus 10 to automatically release or free the surgical anvil buttress “B” from the tissue contacting surface of the anvil plate 70 upon a complete firing of the surgical stapling apparatus 10.

With reference to FIGS. 6-9, during the manufacturing process, with suture release assembly 74 in the open or release configuration (FIGS. 8 and 9), a surgical anvil buttress “B” is laid over the tissue contacting surface of anvil plate 70. Then, a first end of a surgical suture “S1” is inserted into one of the pair of distal recesses 70 e and a second end of surgical suture “S1” is extended across the surgical anvil buttress “B1” (see FIG. 2) and inserted into the other of the pair of distal recesses 70 e. It is contemplated that the first end of surgical suture “S1” may include a knot, stop or the like (not shown) sized so as to not pass through the narrower recess of the distal pair of recesses 70 e.

With the second end of the surgical suture “S1” disposed in the pair of distal recesses 70 e, and with the surgical suture “S1” pulled taught across the surgical anvil buttress “B”, a tool (not shown) is inserted through arcuate slot 75 a of guide plate 75 and engaged with an opening provided in the pin 77 d of release bar 77 c. With reference to FIGS. 6 and 7, the tool is then manipulated to move through or along arcuate slot 75 a of guide plate 75, thereby actuating or moving release bar 77 c and rotating eccentric cam 77 a. As eccentric cam 77 a is rotated, boss 77 b is rotated around the pivot axis of eccentric cam 77 a and acts on the walls of elongate slot 76 b of anchor bar 76 thereby causing anchor bar 76 to pivot. As anchor bar 76 is pivoted, finger 76 c thereof is caused to extend into or overlies one of the distal recesses 70 e and to pinch the second end of the surgical suture disposed therewithin. Meanwhile, release bar 77 c has been moved to a position extending across knife slot 70 b of anvil plate 70. Suture release assembly 74 is now in the locking or anchoring configuration, as described above. The distal recess 70 e that cooperates with the finger 76 c is desirably relatively wide so as to allow the suture “S1” to easily pass into and out of the recess 70 e when the 76 anchor bar is away from the recess 70 e. The other distal recess 70 e, arranged on the opposite lateral side of the anvil plate 70, may be the same size, or may be small enough to cinch the suture “S1” and hold the suture in place to facilitate assembly.

In operation, with surgical anvil buttress “B1” secured against the lower surface of anvil plate 70, during firing of surgical stapling apparatus 10, as drive assembly 50 is advanced (i.e., moved from a proximal-most position to a distal-most position), knife blade 66 slices through a central section of the proximal suture “S2”, thereby freeing the proximal end of the surgical anvil buttress “B1” from anvil assembly 20. During use, as the firing stroke of surgical stapling apparatus 10 is nearing completion and as drive assembly 50 approaches a distal end of knife slot 70 b of anvil plate 70, as seen in FIG. 9, drive assembly 50 contacts release bar 77 c, urging release bar 77 c and, in turn, eccentric cam 77 a to rotate about the pivot axis thereof. As eccentric cam 77 a is rotated, boss 77 b is rotated around the pivot axis of eccentric cam 77 a and acts on the walls of elongate slot 76 b of anchor bar 76 thereby causing anchor bar 76 to pivot. As anchor bar 76 is pivoted, finger 76 c thereof is caused to move away from the relatively wider distal recess 70 e and to release the second end of the surgical suture “S” disposed therewithin. With the second end of surgical suture “S” released or free, the distal end of the surgical anvil buttress “B1” is free to separate from the tissue contacting surface of anvil plate 70.

As seen in FIGS. 1 and 2, cartridge assembly 18 includes a carrier 80 defining an elongated support channel 80 a. Elongated support channel 80 a of carrier 80 receives a staple cartridge 82 therein. Corresponding tabs and slots formed along staple cartridge 82 and carrier 80 function to retain staple cartridge 82 within carrier 80. A pair of support struts formed on and extending from staple cartridge 82 are positioned to rest on side walls of carrier 80 to further stabilize staple cartridge 82 within support channel 80 a of carrier 80. Staple cartridge 82 includes retention slots 82 a formed therein for receiving a plurality of fasteners 84 and pushers 86. A plurality of spaced apart longitudinal slots 82 b extend through staple cartridge 82 to accommodate upstanding cam wedges 90 a of an actuation sled 90. The actuation sled 90 includes a central upstanding wedge or wall 90 b. Central wall 90 b defines a distal notch or shoulder 90 c formed therein (See FIG. 2).

A central longitudinal slot 82 c is formed in and extends along the length of staple cartridge 82 to facilitate passage of central wall portion 62 of head 60 therethrough. During operation of surgical stapler 10, actuation sled 90 translates through longitudinal slots 82 b of staple cartridge 82 to advance cam wedges 90 a into sequential contact with pushers 92, to cause pushers 92 to translate vertically within retention slots 82 a and urge fasteners 84 (e.g., staples) from slots 82 a into the staple forming cavities 70 a of anvil plate 70 of anvil assembly 20.

With continued reference to FIGS. 1 and 2, staple cartridge 82 defines a proximal pair of recesses 82 e formed near a proximal end thereof and disposed, one each, on opposed sides of longitudinal slot 82 c. Staple cartridge 82 further defines a distal pair of recesses 82 f formed near a distal end thereof and disposed, one each, on opposed sides of longitudinal slot 82 c. In one embodiment, at least one of the recesses of each of the proximal pair of recesses 82 e and the distal pair of recesses 82 f is preferably non-circular and constricting or otherwise arranged so as to frictionally engage and/or pinch an anchor “S”.

As seen in FIGS. 1 and 2B, cartridge assembly 18 further includes a surgical cartridge buttress “B2”, pledget or the like operatively secured to an upper surface or tissue contacting surface of staple cartridge 82, by anchors “S3” and “S4”, to overlie at least some of staple pockets 82 a and/or at least a portion of a length of longitudinal slot 82 c. In particular, an anchor “S4” is wrapped around a proximal portion of surgical cartridge buttress “B2” and cinched in each of the proximal pair of recesses 82 e and an anchor “S3” is wrapped around a distal portion of the surgical cartridge buttress “B2” and cinched in each of the distal pair of recesses 82 f.

In one particular embodiment, a first end of each anchor “S” includes a knot, stop or the like (not shown) sized so as to not pass through one recess of the proximal pair of recesses 82 e and a second end of each anchor “S” passes over, and transversely across, surgical cartridge buttress “B2”, at least once, and back through the other recess of the proximal pair of recesses 82 e. For example, the second end of each anchor “S” may be pinched or cinched in the other recess of the proximal pair of recesses 82 e so as to anchor the second end of the anchor “S” and secure the surgical cartridge buttress “B2” against the tissue contacting surface of staple cartridge 82. Similarly, an anchor “S3” is used to extend transversely across surgical cartridge buttress “B2” and into engagement with the distal pair of recesses 82 f.

In a further embodiment, the release assembly is arranged to cut the suture “S.” The arcuate slot 75 a on the guide plate 75 extends in the opposite direction so that it is arranged to drive the anchor bar 95 toward the suture “S.” The surface of the anchor bar 76 that faces the suture S includes a sharpened edge and cuts the suture when actuated by the drive assembly.

Surgical cartridge buttress “B2” includes a proximal pair of notches formed in side edges aligned with the proximal pair of recesses 82 e of staple cartridge 82, a distal pair of notches formed in side edges thereof aligned with the distal pair of recesses 82 f of staple cartridge 82, and a proximal notch formed in a proximal edge thereof aligned with longitudinal slot 82 c when surgical cartridge buttress “B2” is secured to staple cartridge 82. Surgical cartridge buttress “B2” further includes a tongue or tab extending from a distal edge thereof to facilitate with the attachment of surgical cartridge buttress “B2” to staple cartridge 82 during the assembly process. It is contemplated that a width of surgical cartridge buttress “B2” may be reduced in a proximal portion thereof. It is further contemplated that the tongue is removed from surgical cartridge buttress “B2” following securement of surgical cartridge buttress “B2” to staple cartridge 82 and prior to packaging or shipment.

As seen in FIGS. 2 and 10-14, cartridge assembly 18 further includes a cartridge release assembly 94 supported in and near a distal end of staple cartridge 82. Release assembly 94 includes a lock or anchor bar 95 pivotally connected to staple cartridge 82. Anchor bar 95 includes a body portion 95 a having a finger 95 b extending from an edge thereof. Finger 95 b is in operative registration with one of the distal pair of recesses 82 f, preferably, the one of the distal pair of recesses having the relatively larger width dimension.

Release assembly 94 further includes an anchor bar actuation member 97 pivotally connected to anchor bar 95 (as seen in FIGS. 11 and 12). Actuation member 97 includes a first cam surface 97 a located along a proximal edge of actuation member 97 and extending across central longitudinal slot 82 c of staple cartridge 82, and a second eccentric cam surface 97 b extending distally and laterally from actuation member 97 in close proximity to the one of the distal pair of recesses 82 f that is operatively associated with finger 95 b of anchor bar 95. First cam surface 97 a of actuation member 97 is substantially arcuate or convex. Actuation member 97 defines an aperture or opening 97 c configured and dimensioned to receive a pin 95 c of anchor bar 95 therein so as to anchor bar 95 and actuation member 97 to pivot or rotate relative to one another.

In operation, rotation of actuation member 97 in a first direction, about its pivot point, results in second cam surface 97 b pressing against a surface 82 g (see FIGS. 13 and 14) of staple cartridge 82 and thus moving finger 95 b at least partially over and/or across the one of the distal pair of recesses 82 f associated therewith.

As seen in FIG. 13, suture release assembly 94 includes a locking or anchoring configuration wherein first cam surface 97 a of actuation member 97 extends into and across central longitudinal slot 82 c of staple cartridge 82, wherein second cam surface 97 b of actuation member 97 is pressed against surface 82 g of staple cartridge 82, and thus finger 95 b of anchor bar 95 extends into or overlies the respective one of the pair of distal recesses 82 f in operative registration therewith. Fastener release assembly 94 may be maintained in the locking or anchoring configuration by way of a biasing member or a detent that engages actuation member 97 in a manner so as to keep actuation member 97 in the locked or anchoring configuration. When in such a locked or anchoring configuration, the suture “S3” may be urged into recess 82 f of staple cartridge 82. It is contemplated that suture release assembly 94 may include a friction fit or snap fit feature for maintaining and/or retaining suture release assembly 94 in the locking or anchoring configuration at all times following the manufacturing/assembly process and prior to a complete firing of surgical stapling apparatus 10.

As seen in FIGS. 12 and 14, suture release assembly 94 includes an open or release configuration wherein finger 95 b of anchor bar 95 does not extend into or overlie the respective one of the pair of distal recesses 82 f in operative registration therewith, first cam surface 97 a of actuation member 97 does not extend into and across central longitudinal slot 82 c of staple cartridge 82, and second cam surface 97 b of actuation member 97 is not pressed against surface 82 g of staple cartridge 82.

Suture release assembly 94 is used by a manufacturer during the assembly process of surgical stapling apparatus 10 to secure, with an anchor, surgical suture, or tether “S”, a surgical cartridge buttress “B2” (see FIG. 2) to a tissue contacting surface of the staple cartridge 82, and by the end user of surgical stapling apparatus 10 to automatically release or free the surgical cartridge buttress “B2” from the tissue contacting surface of the staple cartridge 82 upon a complete firing of the surgical stapling apparatus 10.

With reference to FIGS. 10-14, during the manufacturing process, with suture release assembly 94 in the open or release configuration, a surgical cartridge buttress “B2” is laid over the tissue contacting surface of staple cartridge 82. Then, a first end of a surgical suture “S” is inserted into the relatively narrower of the pair of distal recesses 82 f and a second end of surgical suture “S” is extended across the surgical cartridge buttress “B2” and inserted into the relatively wider of the pair of distal recesses 82 f. It is contemplated that the first end of surgical suture “S” may include a knot, stop or the like (not shown) sized so as to not pass through the narrower recess of the distal pair of recesses 82 f.

As seen in FIG. 11, staple cartridge 82 includes an access opening 83 formed therein which is used to insert and receive suture release assembly 94 therein and to provide access to actuation member 97. With the second end of the surgical suture “S” disposed in the relatively wider of the pair of distal recesses 82 f, and with the surgical suture “S” pulled taught across the surgical cartridge buttress “B2,” actuation member 97 is rotated about the pivot axis causing first cam surface 97 a of actuation member 97 to extend into and across central longitudinal slot 82 c of staple cartridge 82 and causing second cam surface 97 b of actuation member 97 to press against surface 82 g (see FIGS. 13 and 14) of staple cartridge 82. In so doing, anchor bar 95 is pivoted by an amount sufficient for finger 95 b of anchor bar 95 to extend into or overlies the respective one of the pair of distal recesses 82 f in operative registration therewith thereby pinch the second end of the surgical suture disposed therewithin. Suture release assembly 94 is now in the locking or anchoring configuration, as described above.

In operation, with surgical cartridge buttress “B1” secured against the tissue contacting surface of staple cartridge 82, during firing of surgical stapling apparatus 10, as drive assembly 50 is advanced (i.e., moved from a proximal-most position to a distal-most position), knife blade 66 slices through a central section of the proximal suture “S4”, thereby freeing the proximal end of the surgical cartridge buttress “B2” from staple cartridge 82. During use, as the firing stroke of surgical stapling apparatus 10 is nearing completion and as drive assembly 50 approaches a distal end of central longitudinal slot 82 c of staple cartridge 82, as seen in FIG. 14, drive assembly 50 contacts first cam surface 97 a of actuation member 97, urging actuation member 97 to rotate. Second cam surface 97 b of actuation member 97 also rotates about the pivot axis of pivot pin 95 c thereof. As eccentric second cam surface 97 b is rotated about the pivot axis second cam surface 97 b, the distance between the pivot pin 95 c and the surface 82 g of staple cartridge 82 is reduced thereby pivoting anchor bar 95 about pivot pin 95 c. As anchor bar 95 is pivoted, finger 95 c thereof is caused to move away from the relatively wider distal recess 82 f and to release the second end of the surgical suture “S” disposed therewithin. With the second end of surgical suture “S” released or free, the distal end of the surgical cartridge buttress “B2” is free to separate from the tissue contacting surface of staple cartridge 82. The distal recesses 82 f that is in operative registration with finger 95 b of anchor bar 95 is dimensioned so that, notwithstanding the rotation of anchor bar 95, the suture “S3” is not cinched therewithin.

As drive assembly 50 is advanced from the proximal position to the distal position, knife blade 66 thereof slices or cuts longitudinally through both surgical anvil buttress “B1” and surgical cartridge buttress “B2”, thereby dividing the buttresses “B1, B2” substantially in half. Additionally, as drive assembly 50 is advanced from a proximal-most position to a distal-most position, upstanding cam wedges 90 a of actuation sled 90 actuates pushers 92, to cause pushers 92 to translate vertically within retention slots 82 a and urge fasteners 84 from slots 82 a. As fasteners 84 (e.g., staples) are urged from slots 82 a of staple cartridge 82, legs of fasteners 84 penetrate and pass through both surgical anvil buttress “B1” and surgical cartridge buttress “B2”, through any tissue (not shown) interposed between surgical anvil buttress “B1” and surgical cartridge buttress “B2”, and are formed against or within staple forming cavities 70 a of anvil plate 70 of anvil assembly 20. Buttresses “B1, B2” preferably include perforations that divide the buttresses and facilitate removal of the apparatus from the tissue.

According to the present disclosure, surgical anvil buttress “B1” and/or surgical cartridge buttress “B2” is pre-loaded (i.e., from the manufacturer) onto anvil assembly 20 or cartridge assembly 18, respectively, of the loading unit 16. After the loading unit is fired, an additional unfired loading unit, with or without buttresses “B”, can be loaded onto the surgical apparatus. In certain embodiments, the replaceable loading unit is a removable cartridge that can be inserted into support channel of carrier 80. A buttress and release assembly may be pre-loaded onto the removable cartridge and means for the user of the surgical apparatus to load a buttress onto the anvil assembly can be provided. For example, a buttress having an adhesive can be used. Additional or replacement buttresses “B” for anvil assembly 20 and/or cartridge assembly 18 may be secured to either anvil assembly 20 or cartridge assembly 18 as needed or desired.

In a further embodiment, the release assembly may be arranged to cut the suture “S.” The cam surface 97 b on the actuation member 97 may be arranged to cam the anchor bar 95 toward the suture “S.” The surface of the anchor bar 97 that faces the suture “S” may include a sharpened edge and may cut the suture when actuated by the drive assembly.

Turning now to FIGS. 15-25, a loading unit according to another embodiment of the present disclosure, for surgical stapling apparatus 10, is generally designated as 116. Loading unit 116 is substantially similar to loading unit 16 and will only be discussed in detail herein to the extent necessary to identify differences in construction and operation.

As seen in FIGS. 15-20, anvil assembly 120 of loading unit 116 includes a suture release assembly 174 disposed between anvil plate 170 and cover plate 172 at a location in operative registration with the distal pair of recesses 170 e. Suture release assembly 174 includes a link arm 175 pivotally connected to anvil plate 170 (as seen in FIG. 18) and/or optionally cover plate 172. Link arm 175 includes a body portion 175 a defining a pocket or recess 175 c formed in a first side edge 175 b thereof and a camming surface 175 d defined substantially along an adjacent side or proximal edge thereof. Pocket 175 c has a substantially arcuate, circular or rounded profile. As seen in FIGS. 18 and 20, link arm 175 includes a pivot pin 175 e extending from body portion 175 a for pivotally connecting link arm 175 to anvil assembly 120.

Release assembly 174 further includes a pusher bar 177 pivotally connected to link arm 175 and slidably disposed between anvil plate 170 and cover plate 172. Pusher bar 177 includes a body portion 177 a having a substantially rectangular configuration and a head 177 b, extending from a corner of body portion 177 a, and having a substantially circular or rounded configuration. Head 177 b of pusher bar 177 is configured and dimensioned for pivotable and/or rotatable connection in pocket 175 c of link arm 175.

As seen in FIG. 19, suture release assembly 174 includes an unactuated configuration wherein pusher bar 177 does not extend into or overlie the respective one of the pair of distal recesses 170 e in operative registration therewith, and a longitudinal axis of link arm 175 is oriented substantially parallel with a longitudinal axis of loading unit 116. It is contemplated that suture release assembly 174 may include a friction fit or snap fit feature for maintaining and/or retaining suture release assembly 174 in the locking or anchoring configuration at all times following the manufacturing/assembly process and prior to a complete firing of the surgical stapling apparatus.

As seen in FIG. 20, suture release assembly 174 includes an actuated configuration wherein pusher bar 177 extends into or overlies the respective one of the pair of distal recesses 170 e in operative registration therewith, and a longitudinal axis of link arm 175 is oriented substantially transverse to the longitudinal axis of loading unit 116.

With reference to FIGS. 15-20, during the manufacturing process, with suture release assembly 174 in the unactuated configuration, a surgical anvil buttress (not shown) is laid over the tissue contacting surface of anvil plate 170. Then, a first end of a surgical suture “S1” is inserted into one of the pair of distal recesses 170 e and a second end of surgical suture “S1” is extended across the surgical anvil buttress (not shown) and inserted into the other of the pair of distal recesses 170 e. It is contemplated that each of the pair of distal recesses 170 e is an open ended constricting slot so as to frictionally grip or cinch a surgical suture “S1” disposed therein.

In operation, with a surgical anvil buttress (not shown) secured against the lower surface of anvil plate 170, during firing of the surgical stapling apparatus, as drive assembly 150 is advanced (i.e., moved from a proximal-most position to a distal-most position), knife blade 166 slices through a central section of the proximal suture (not shown), thereby freeing the proximal end of the surgical anvil buttress (not shown) from anvil assembly 120. During use, as the firing stroke of the surgical stapling apparatus is nearing completion and as drive assembly 150 approaches a distal-most end of knife slot 170 b of anvil plate 170, as seen in FIG. 20, drive assembly 150 contacts camming surface 175 d of link arm 175, thus urging link arm 175 to rotate or pivot around the pivot pin and, in turn, urging pusher bar 177 to translate in the direction of the slot. As pusher bar 177 is translated, pusher bar 177 comes into contact with and urges the second end of suture “S1” out of the distal recess 170 e that is registration therewith to release the second end of suture “S1” therefrom. With the second end of surgical suture “S1” released or free from distal recess 170 e, the distal end of the surgical anvil buttress “B1” is free to separate from the tissue contacting surface of anvil plate 170.

As seen in FIGS. 15, 16 and 21-25, cartridge assembly 118 of loading unit 116 includes a cartridge release assembly 194 supported in and near a distal end of staple cartridge 182. Release assembly 194 includes a retainer 195 supported in a distal end of staple cartridge 182 at a location near a distal end of longitudinal slot 182 c and at least partially extending thereacross. Retainer 195 includes a body portion 195 a, a boss 195 b extending from a surface thereof, and defines a channel or recess 195 c formed in a surface thereof and extending through a side thereof. When supported in staple cartridge 182, recess 195 c of retainer 195 is in registration with one of the pair of distal recesses 182 f of staple cartridge 182.

Release assembly 194 further includes a pusher member 196 having a head portion 196 a pivotally connected to boss 195 b of retainer 195. Pusher member 196 further includes a first leg member 196 b extending from head portion 196 a and a second leg member 196 c connected to a free end of first leg member 196 b via a living hinge connection 196 d. Pusher member 196 further includes piston 196 e connected to a free end of second leg member 196 c via a living hinge connection 196 f. Piston 196 e is slidably disposed and translatable within recess 195 c of retainer 195. In certain other embodiments, the pusher is a linkage assembly having a first link pivotably connected to the cartridge at one end. The other end of the first link is pivotably connected to a first end of a second link. The opposite, second, end of the second link is confined in the recess of the retainer.

As seen in FIG. 24, release assembly 194 includes an unactuated configuration wherein piston 196 e does not extend into or overlie the respective one of the pair of distal recesses 182 f, and first leg member 196 b and second leg member 196 c are angled with respect to one another and project proximally along longitudinal slot 182 c of staple cartridge 182. It is contemplated that suture release assembly 194 may include a friction fit or snap fit feature for maintaining and/or retaining suture release assembly 194 in the locking or anchoring configuration at all times following the manufacturing/assembly process and prior to a complete firing of the surgical stapling apparatus.

As seen in FIG. 25, suture release assembly 194 includes an actuated configuration wherein piston 196 e extends into or overlies the respective one of the pair of distal recesses 182 f in operative registration therewith, and first leg member 196 b and second leg member 196 c are extended substantially along a common axis.

With reference to FIGS. 21-25, during the manufacturing process, with suture release assembly 194 in the unactuated configuration, a surgical cartridge buttress (not shown) is laid over the tissue contacting surface of staple cartridge 182. Then, a first end of a surgical suture “S3” is inserted into one of the pair of distal recesses 182 f and a second end of surgical suture “S3” is extended across the surgical cartridge buttress and inserted into the other of the pair of distal recesses 182 f. It is contemplated that at least the recess 182 f that is adjacent the retainer 195 is an open ended constricting slot so as to frictionally grip or cinch a surgical suture “S3” disposed therein.

In operation, with surgical cartridge buttress (not shown) secured against the tissue contacting surface of staple cartridge 182, during firing of surgical stapling apparatus 10, as drive assembly 150 is advanced (i.e., moved from a proximal-most position to a distal-most position), knife blade 166 slices through a central section of a proximal suture (not shown), thereby freeing the proximal end of the surgical cartridge buttress from staple cartridge 182. During use, as the firing stroke of surgical stapling apparatus 10 is nearing completion and as drive assembly 150 approaches a distal end of central longitudinal slot 182 c of staple cartridge 182, as seen in FIG. 25, drive assembly 150 contacts living hinge connection 196 d between first leg member 196 b and second leg member 196 c. As drive assembly 150 is further advanced distally, drive assembly 150 presses against living hinge connection 196 d, causing first leg member 196 b and second leg member 196 c to extend. As first leg member 196 b and second leg member 196 c extend, piston 196 e is translated through recess 195 c of retainer 195. As piston 196 e is translated through recess 195 c of retainer 195, piston 196 e engages the second end of suture “S3” and urges suture “S3” out of the distal recess 182 f that is registration therewith to release the second end of suture “S3” therefrom. With the second end of surgical suture “S3” released or free from distal recess 182 f, the distal end of the surgical cartridge buttress “B” is free to separate from the tissue contacting surface of staple cartridge 182.

Turning now to FIGS. 26-29, a loading unit according to another embodiment of the present disclosure, for surgical stapling apparatus 10, is generally designated as 216. Loading unit 216 is substantially similar to loading unit 16 or 116 and will only be discussed in detail herein to the extent necessary to identify differences in construction and operation.

As seen in FIGS. 26-29, anvil assembly 220 of loading unit 216 includes a release assembly 274 disposed between anvil plate 270 and cover plate 272 at a location in operative registration with the distal pair of recesses 270 e. Release assembly 274 includes a cam 275 pivotally connected to anvil plate 270 and/or cover plate 272. Cam 275 includes a body portion 275 a having an ovular profile and defining a cam surface 275 b that is in operative association with one of the distal pair of recesses 270 e. Cam 275 further includes a finger or stem 275 c projecting at an angle from a lateral edge of body portion 275 a.

Release assembly 274 further includes a pusher 277 slidably disposed between anvil plate 270 and cover plate 272. As seen in FIGS. 27-29, pusher 277 may be slidably disposed within longitudinal slot 270 b of anvil plate 270 a. Pusher 277 includes a cam arm 277 a extending substantially in a distal direction. Cam arm 277 a is configured and dimensioned to engage and/or act on finger 275 c extending from cam 275.

As seen in FIG. 28, suture release assembly 274 includes an unactuated configuration wherein body portion 275 a of cam 275 does not extend into or overlie the respective one of the pair of distal recesses 270 e in operative registration therewith, and pusher 277 is in a retracted or non-advanced position. As seen in FIG. 28, cam arm 277 a of pusher 277 is adjacent finger 275 c and may, although not necessarily, be in contact with finger 275 c of cam 275.

As seen in FIG. 29, suture release assembly 274 includes an actuated configuration wherein body portion 275 a of cam 275 extends into or overlies the respective one of the pair of distal recesses 270 e in operative registration therewith, and pusher 277 is in an advanced position. As seen in FIG. 29, when pusher 277 is in the advanced position, cam arm 277 a of pusher 277 has engaged finger 275 c of cam 275 to rotate body portion 275 a of cam 275.

In operation, with an surgical anvil buttress (not shown) secured against the lower surface of anvil plate 270, during firing of the surgical stapling apparatus, as drive assembly 250 approaches a distal-most end of knife slot 270 b of anvil plate 270, drive assembly 250 contacts pusher 277, thus driving pusher 277 distally. As pusher 277 is driven distally, as seen in FIGS. 28 and 29, cam arm 277 a of pusher 277 engages finger 275 c of cam 275 to rotate or pivot cam 275. As cam 275 is rotated, cam surface 275 b of cam 275 comes into contact with and urges the second end of suture “S1” out of the distal recess 270 e that is registration therewith to release the second end of suture “S1” therefrom. With the second end of surgical suture “S1” released or free from distal recess 270 e, the distal end of the surgical anvil buttress is free to separate from the tissue contacting surface of anvil plate 270.

Turning now to FIGS. 30 and 31, a loading unit according to another embodiment of the present disclosure, for surgical stapling apparatus 10, is generally designated as 316. Loading unit 316 is substantially similar to loading unit 16, 116 or 216 and will only be discussed in detail herein to the extent necessary to identify differences in construction and operation.

As seen in FIGS. 30 and 31, anvil assembly 320 of loading unit 316 includes a release assembly 374 disposed between anvil plate 370 and the cover plate at a location in operative registration with the distal pair of recesses 370 e. Release assembly 374 includes a body portion 374 a slidably disposed within longitudinal slot 370 b of anvil plate 370 a. Release assembly 374 further includes a head portion 374 b connected to or extending from a distal surface of body portion 374 a. Head portion 374 b defines a cam surface 374 c along a side edge thereof that is configured and dimensioned for operatively association with one of the distal pair of recesses 370 e formed in anvil plate 370 a. Cam surface 374 c may have an arcuate, curved or sinusoidal profile.

As seen in FIG. 30, suture release assembly 374 includes an unactuated configuration wherein body portion 374 a is retracted and cam surface 374 c does not extend into or across the respective one of the pair of distal recesses 370 e in operative registration therewith.

As seen in FIG. 31, suture release assembly 374 includes an actuated configuration wherein body portion 374 a is advanced distally and cam surface 374 c extends into or overlies the respective one of the pair of distal recesses 370 e in operative registration therewith.

In operation, with a surgical anvil buttress (not shown) secured against the lower surface of anvil plate 370, during firing of the surgical stapling apparatus, as drive assembly 350 approaches a distal-most end of knife slot 370 b of anvil plate 370, as seen in FIGS. 30 and 31, drive assembly 350 contacts body portion 374 a of release assembly 374, thus driving head portion 374 b distally. As head portion 374 b is driven distally, cam surface 374 c comes into contact with and urges the second end of suture “S1” out of the distal recess 370 e that is registration therewith to release the second end of suture “S1” therefrom. With the second end of surgical suture “S10” released or free from distal recess 370 e, the distal end of the surgical anvil buttress is free to separate from the tissue contacting surface of anvil plate 370.

In a further embodiment, the driving head portion may include a sharpened edge instead of cam surface 374 c. As the driving head portion is moved distally, the suture “S1” is caught between the sharpened edge of the driving head portion and the side of the distal recess 370 e, severing the suture “S1.”

Turning now to FIGS. 32-38, a loading unit according to another embodiment of the present disclosure, for surgical stapling apparatus 10, is generally designated as 416. Loading unit 416 is substantially similar to loading unit 16, 116, 216 or 316 and will only be discussed in detail herein to the extent necessary to identify differences in construction and operation.

As seen in FIGS. 32-38, cartridge assembly 418 of loading unit 416 includes a cartridge release assembly 494 supported in and near a distal end of staple cartridge 482. Release assembly 494 includes a retainer 495 supported in a distal end of staple cartridge 482 at a location near a distal end of longitudinal slot 482 c and at least partially extending thereacross. Retainer 495 includes a body portion 495 a, a boss 495 b extending from a surface thereof, and defines a channel or recess 495 c formed in a surface thereof and extending through a side thereof. Body portion 495 a of retainer 495 defines a slot 495 d formed in opposed sides thereof and which are configured to receive a suture therein. When supported in staple cartridge 482, recess 495 c of retainer 495 is in registration with one of the pair of distal recesses 482 f of staple cartridge 482, and slots 495 d of retainer 495 are in registration with the pair of distal recesses 482 f of staple cartridge 482 (see FIG. 32).

Release assembly 494 further includes a cam member 496 having a head portion 496 a pivotally connected to boss 495 b of retainer 495. Cam member 496 further includes a body portion 496 b extending from head portion 496 a. Body portion 496 b defines a first cam surface 496 c and a second cam surface 496 d each extending substantially tangentially to an axis of rotation of cam member 496.

Release assembly 494 further includes a sled 497 slidably disposed within channel 495 c of retainer 495. Sled 497 includes a body portion 497 a defining a cam surface 497 b oriented to operatively engage second cam surface 496 d of cam member 496, and a side wall 497 c in registration with the one of the pair of distal recesses 482 f of staple cartridge 482 that is in registration with recess 495 c of retainer 495.

As seen in FIG. 37, release assembly 494 includes an unactuated configuration wherein first cam surface 496 c of cam member 496 extends across longitudinal slot 482 c staple cartridge 482, side wall 497 c of sled 497 does not extend into or over the one of the pair of distal recesses 482 f of staple cartridge 482 that is in registration therewith, and second cam surface 496 d of cam member 496 is substantially in flush contact with cam surface 497 b of sled 497.

As seen in FIG. 38, release assembly 494 includes an actuated configuration wherein first cam surface 496 c of cam member 496 does not substantially extend across longitudinal slot 482 c of staple cartridge 482, side wall 497 c of sled 497 extends into or over the one of the pair of distal recesses 482 f of staple cartridge 482 that is in registration therewith, and second cam surface 496 d of cam member 496 is spaced away from cam surface 497 b of sled 497.

With reference to FIGS. 32-38, during the manufacturing process, with suture release assembly 494 in the unactuated configuration, a surgical cartridge buttress (not shown) is laid over the tissue contacting surface of staple cartridge 482. Then, a first end of a surgical suture “S3” is inserted into one of the pair of distal recesses 482 f and a second end of surgical suture “S3” is extended across the surgical cartridge buttress and inserted into the other of the pair of distal recesses 482 f. It is contemplated that at least the distal recesses 482 f adjacent the side wall 497 c is an open ended constricting slot so as to frictionally grip or cinch a surgical suture “S3” disposed therein.

In operation, with a surgical cartridge buttress (not shown) secured against the tissue contacting surface of staple cartridge 482, during firing of the surgical stapling apparatus, as drive assembly 450 approaches a distal end of central longitudinal slot 482 c of staple cartridge 482, as seen in FIG. 38, drive assembly 450 contacts second cam surface 496 c of cam member 496 extending across longitudinal slot 482 c of staple cartridge 482.

As drive assembly 450 is further advanced distally, drive assembly 450 presses against first cam surface 496 c of cam member 496, causing cam member 496 to rotate. As cam member 496 is rotated, second cam surface 496 d thereof contacts and presses against cam surface 497 b of sled 497 thus causing sled 497 to translate in recess 495 c of retainer 495. As sled 497 is translated through recess 495 c, side wall 497 c of sled 497 engages the second end of suture “S3” and urges suture “S3” out of the distal recess 482 f that is registration therewith to release the second end of suture “S3” therefrom. With the second end of surgical suture “S3” released or free from distal recess 482 f, the distal end of the surgical cartridge buttress is free to separate from the tissue contacting surface of staple cartridge 482.

According to further embodiments of the present disclosure, it is contemplated that buttresses “B” may be provided or formed with integral wings or tabs extending therefrom for insertion and/or receipt into distal and/or proximal recesses of anvil assembly and/or cartridge assembly. It is further contemplated that sutures “S” may be affixed to, embedded in or other wise connected to buttresses “B.”

Exemplary surgical buttresses “B” for use with the surgical stapling devices disclosed herein are shown and described in commonly assigned U.S. Pat. Nos. 5,542,594; 5,908,427; 5,964,774; and 6,045,560, and commonly assigned U.S. application Ser. No. 11/241,267, filed on Sep. 30, 2005 (now U.S. Patent Publication No. 2006/0085034), and U.S. application Ser. No. 11/248,846, filed on Oct. 12, 2005 (U.S. Patent Publication No. 2006/0135992, now U.S. Pat. No. 7,823,592), the entire contents of each of which is incorporated herein by reference.

Surgical buttresses “B” may be fabricated from a suitable biocompatible and bioabsorbable material. Surgical buttresses “B” may be fabricated from a non-absorbent material which does not retain fluid. Surgical buttresses “B” may be fabricated from “BIOSYN” made from GLYCOMER 631 (a block copolymer), a synthetic polyester composed of glycolide, dioxanone and trimethylene carbonate.

One block of the resulting copolymer contains randomly combined units derived from p-dioxanone (1,4-dioxan-2-one) and trimethylene carbonate (1,3-dioxan-2-one). The second block of the copolymer contains randomly combined units derived from glycolide and p-dioxanone. The resulting polyester is an ABA triblock terpolymer possessing about 60% glycolide, about 14% dioxanone, and about 26% trimethylene carbonate.

It will be understood that various modifications may be made to the embodiments disclosed herein. For example, the stapling apparatus need not apply staples but rather may apply two part fasteners as is known in the art. Further, the length of the linear row of staples or fasteners may be modified to meet the requirements of a particular surgical procedure. Thus, the length of a single stroke of the actuation shaft and/or the length of the linear row of staples and/or fasteners within a disposable loading unit may be varied accordingly. Therefore, the above description should not be construed as limiting, but merely as exemplifications of preferred embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended thereto. 

1. A surgical stapling apparatus, comprising: a housing; a handle supported by the housing; an elongated body extending distally from the housing; a tool assembly at the distal end of the elongated body, the tool assembly having a cartridge assembly including a staple cartridge having a plurality of surgical fasteners therein, and an anvil assembly, at least one of the cartridge assembly and anvil assembly being movable in relation to the other of the cartridge assembly and anvil assembly, wherein the anvil assembly includes an anvil plate, and wherein each of the anvil plate and the staple cartridge define an elongate longitudinal slot; a surgical buttress disposed on a tissue contacting surface of a selected one of the anvil assembly and the staple cartridge, wherein the surgical buttress is secured to the selected one of the anvil assembly and the cartridge assembly by a suture disposed in a retention slot defined in the tissue contacting surface of the selected one of the anvil assembly and the staple cartridge, the suture passing transversely across the surgical buttress; and a release assembly that grips the suture prior to an actuation of a drive assembly movable in the longitudinal slot and including: a first bar extending across the longitudinal slot prior to an actuation of the drive assembly; and a second bar, connected to and actuatable by the first bar, having an end extending at least partially into the retention slot, prior to an actuation of the drive assembly.
 2. The surgical stapling apparatus according to claim 1, wherein the retention slot cinches the suture therein.
 3. The surgical stapling apparatus according to claim 1, wherein as the drive assembly is advanced to a distal position, the drive assembly actuates the first bar of the release assembly which in turn actuates the second bar of the release assembly to release the suture disposed within the retention slot.
 4. The surgical stapling apparatus according to claim 1, wherein the retention slot comprises a hole in the tissue contacting surface of the selected one of the anvil assembly and staple cartridge.
 5. The surgical stapling apparatus according to claim 1, wherein the surgical buttress is disposed on the tissue contacting surface of the staple cartridge and further comprising a second surgical buttress disposed on a tissue contacting surface of the anvil assembly.
 6. The surgical stapling apparatus according to claim 1, further comprising a housing portion removably couplable to the elongated body of the surgical stapling apparatus, the surgical buttress comprising a first surgical buttress disposed on the staple cartridge and further comprising a second surgical buttress disposed on the anvil assembly, the first surgical buttress being pre-loaded on the staple cartridge and the second surgical buttress being pre-loaded on the anvil assembly.
 7. The surgical stapling apparatus according to claim 1, wherein the suture is at least partially disposed in the surgical buttress.
 8. A surgical stapling apparatus, comprising: a housing; a handle supported by the housing; an elongated body extending distally from the housing; a tool assembly at the distal end of the elongated body, the tool assembly having a cartridge assembly including a staple cartridge having a plurality of surgical fasteners therein, and an anvil assembly, at least one of the cartridge assembly and anvil assembly being movable in relation to the other of the cartridge assembly and anvil assembly, wherein the anvil assembly includes an anvil plate, and wherein each of the anvil plate and the staple cartridge define an elongate longitudinal slot; a plurality of sutures; a surgical buttress disposed on a tissue contacting surface of a selected one of the anvil assembly and the staple cartridge, wherein the surgical buttress is secured to the selected one of the anvil assembly and the cartridge assembly by a suture disposed in a retention slot defined in the tissue contacting surface of the selected one of the anvil assembly and the staple cartridge, the suture passing transversely across the surgical buttress; an anvil release assembly and a cartridge release assembly, each of the anvil assembly and the cartridge assembly defining a retention slot, a first suture in a retention slot of the anvil assembly and a second suture in a retention slot of the cartridge assembly, wherein each release assembly includes: a first bar extending across the longitudinal slot prior to an actuation of a drive assembly; and a second bar, connected to and actuatable by the first bar, having an end extending at least partially into the retention slot, prior to an actuation of the drive assembly; wherein as the drive assembly is advanced to the distal position, the drive assembly actuates the first bar of each release assembly which in turn actuates the second bar of each release assembly to release the suture disposed within the retention slot.
 9. The loading unit according to claim 8, wherein each release assembly grips the suture prior to an actuation of the drive assembly.
 10. The surgical stapling apparatus according to claim 8, wherein the retention slot comprises a hole in the tissue contacting surface of the selected one of the anvil assembly and staple cartridge.
 11. The surgical stapling apparatus according to claim 8, wherein the surgical buttress is disposed on the tissue contacting surface of the staple cartridge and further comprising a second surgical buttress disposed on a tissue contacting surface of the anvil assembly.
 12. The surgical stapling apparatus according to claim 8, further comprising a housing portion removably couplable to the elongated body of the surgical stapling apparatus, the surgical buttress comprising a first surgical buttress disposed on the staple cartridge and further comprising a second surgical buttress disposed on the anvil assembly, the first surgical buttress being pre-loaded on the staple cartridge and the second surgical buttress being pre-loaded on the anvil assembly.
 13. The surgical stapling apparatus according to claim 8, wherein the suture is at least partially disposed in the surgical buttress.
 14. A surgical stapling apparatus, comprising: a housing; a handle supported by the housing; an elongated body extending distally from the housing; a tool assembly at the distal end of the elongated body, the tool assembly having a cartridge assembly including a staple cartridge having a plurality of surgical fasteners therein, and an anvil assembly, at least one of the cartridge assembly and anvil assembly being movable in relation to the other of the cartridge assembly and anvil assembly, wherein the anvil assembly includes an anvil plate, and wherein each of the anvil plate and the staple cartridge define an elongate longitudinal slot; a surgical buttress disposed on a tissue contacting surface of a selected one of the anvil assembly and the staple cartridge, wherein the surgical buttress is secured to the selected one of the anvil assembly and the cartridge assembly by a suture disposed in a retention slot defined in the tissue contacting surface of the selected one of the anvil assembly and the staple cartridge, the suture passing transversely across the surgical buttress; and at least one of the anvil assembly and the cartridge assembly includes a constricting, open-ended, side slot configured to grip an end of the suture, and further comprising a release assembly to push the end of the suture out of the retention slot.
 15. The surgical stapling apparatus according to claim 14, wherein each of the anvil assembly and the cartridge assembly includes a release assembly.
 16. The surgical stapling apparatus according to claim 15, wherein each of the anvil assembly and the cartridge assembly define a retention slot, the suture comprising a plurality of sutures including a first suture in a retention slot of the anvil assembly and a second suture in a retention slot of the cartridge assembly.
 17. The surgical stapling apparatus according to claim 14, wherein the retention slot comprises a hole in the tissue contacting surface of the selected one of the anvil assembly and staple cartridge.
 18. The surgical stapling apparatus according to claim 14, wherein the surgical buttress is disposed on the tissue contacting surface of the staple cartridge and further comprising a second surgical buttress disposed on a tissue contacting surface of the anvil assembly.
 19. The surgical stapling apparatus according to claim 14, further comprising a housing portion removably couplable to the elongated body of the surgical stapling apparatus, the surgical buttress comprising a first surgical buttress disposed on the staple cartridge and further comprising a second surgical buttress disposed on the anvil assembly, the first surgical buttress being pre-loaded on the staple cartridge and the second surgical buttress being pre-loaded on the anvil assembly.
 20. The surgical stapling apparatus according to claim 14, wherein the suture is at least partially disposed in the surgical buttress.
 21. A surgical stapling apparatus, comprising: a housing; a handle supported by the housing; an elongated body extending distally from the housing; a tool assembly at the distal end of the elongated body, the tool assembly having a cartridge assembly including a staple cartridge having a plurality of surgical fasteners therein, and an anvil assembly, at least one of the cartridge assembly and anvil assembly being movable in relation to the other of the cartridge assembly and anvil assembly, wherein the anvil assembly includes an anvil plate, and wherein each of the anvil plate and the staple cartridge define an elongate longitudinal slot; and a surgical buttress disposed on a tissue contacting surface of a selected one of the anvil assembly and the staple cartridge, wherein the surgical buttress is secured to the selected one of the anvil assembly and the cartridge assembly by a suture disposed in a retention slot defined in the tissue contacting surface of the selected one of the anvil assembly and the staple cartridge, the suture passing transversely across the surgical buttress, wherein the surgical buttress defines a notch that is open at a lateral side of the surgical buttress, the suture extending into the notch.
 22. The surgical stapling apparatus according to claim 21, wherein the surgical buttress is disposed on the tissue contacting surface of the staple cartridge and the retention slot defines a notch that is open at a lateral side of the staple cartridge, the suture extending from the notch of the surgical buttress into the notch of the staple cartridge.
 23. The surgical stapling apparatus according to claim 22, further comprising a second surgical buttress is disposed on a tissue contacting surface of the anvil assembly.
 24. The loading unit according to claim 21, further comprising a release assembly the grips the suture prior to an actuation of a drive assembly movable in the longitudinal slot.
 25. The surgical stapling apparatus according to claim 21, wherein each of the anvil assembly and the cartridge assembly includes a release assembly.
 26. The surgical stapling apparatus according to claim 25, wherein each of the anvil assembly and the cartridge assembly define a retention slot, the suture comprising a plurality of sutures including a first suture in a retention slot of the anvil assembly and a second suture in a retention slot of the cartridge assembly.
 27. The surgical stapling apparatus according to claim 21, wherein the retention slot comprises a hole in the tissue contacting surface of the selected one of the anvil assembly and staple cartridge.
 28. The surgical stapling apparatus according to claim 21, wherein the surgical buttress is disposed on the tissue contacting surface of the staple cartridge and further comprising a second surgical buttress disposed on a tissue contacting surface of the anvil assembly.
 29. The surgical stapling apparatus according to claim 21, further comprising a housing portion removably couplable to the elongated body of the surgical stapling apparatus, the surgical buttress comprising a first surgical buttress disposed on the staple cartridge and further comprising a second surgical buttress disposed on the anvil assembly, the first surgical buttress being pre-loaded on the staple cartridge and the second surgical buttress being pre-loaded on the anvil assembly.
 30. A loading unit for use with a surgical stapling apparatus, the loading unit comprising: a tool assembly having a cartridge assembly including a cartridge having a plurality of surgical fasteners therein, and an anvil assembly, at least one of the cartridge assembly and the anvil assembly being movable in relation to the other of the cartridge assembly and anvil assembly, wherein the anvil assembly includes an anvil plate and, wherein each of the anvil plate and the staple cartridge define an elongate longitudinal slot; a surgical buttress disposed on a tissue contacting surface of at least one of the anvil assembly and the staple cartridge, wherein the surgical buttress is secured to the selected one of the anvil assembly and the cartridge assembly by a suture disposed in a retention slot defined in the tissue contacting surface of the selected one of the anvil assembly and the staple cartridge, the suture passing transversely across the surgical buttress; a release assembly that grips the suture prior to an actuation of a drive assembly movable in the longitudinal slot including: a first bar extending across the longitudinal slot prior to an actuation of the drive assembly, the drive assembly being movable in the longitudinal slot; and a second bar, connected to and actuatable by the first bar, having an end extending at least partially into the retention slot, prior to an actuation of the drive assembly.
 31. The loading unit according to claim 30, wherein as the drive assembly is advanced to a distal position, the drive assembly actuates the first bar of the release assembly which in turn actuates the second bar of the release assembly to release the suture disposed within the retention slot.
 32. The loading unit according to claim 30, wherein each of the anvil assembly and the cartridge assembly includes a release assembly.
 33. The loading unit according to claim 30, further comprising a housing portion removably couplable to an elongated body of the surgical stapling apparatus, the surgical buttress comprising a first surgical buttress disposed on the staple cartridge and further comprising a second surgical buttress disposed on the anvil assembly, the first surgical buttress being pre-loaded on the staple cartridge and the second surgical buttress being pre-loaded on the anvil assembly.
 34. The loading unit according to claim 30, wherein the suture is at least partially disposed in the surgical buttress.
 35. A loading unit for use with a surgical stapling apparatus, the loading unit comprising: a tool assembly having a cartridge assembly including a cartridge having a plurality of surgical fasteners therein, and an anvil assembly, at least one of the cartridge assembly and the anvil assembly being movable in relation to the other of the cartridge assembly and anvil assembly, wherein the anvil assembly includes an anvil plate and, wherein each of the anvil plate and the staple cartridge define an elongate longitudinal slot; a surgical buttress disposed on a tissue contacting surface of at least one of the anvil assembly and the staple cartridge, wherein the surgical buttress is secured to the selected one of the anvil assembly and the cartridge assembly by a suture disposed in a retention slot defined in the tissue contacting surface of the selected one of the anvil assembly and the staple cartridge, the suture passing transversely across the surgical buttress; each of the anvil assembly and the cartridge assembly including a release assembly, each release assembly including: a first bar extending across the longitudinal slot prior to an actuation of a drive assembly; and a second bar, connected to and actuatable by the first bar, having an end extending at least partially into the retention slot, prior to an actuation of the drive assembly, wherein as the drive assembly is advanced to the distal position, the drive assembly actuates the first bar of each release assembly which in turn actuates the second bar of each release assembly to release the suture disposed within the retention slot.
 36. The loading unit according to claim 35, wherein each of the anvil assembly and the cartridge assembly define a retention slot, the suture comprising a plurality of sutures including a first suture in a retention slot of the anvil assembly and a second suture in a retention slot of the cartridge assembly.
 37. The loading unit according to claim 35, wherein the release assembly grips the suture prior to an actuation of a drive assembly movable in the longitudinal slot.
 38. The loading unit according to claim 35, further comprising a housing portion removably couplable to an elongated body of the surgical stapling apparatus, the surgical buttress comprising a first surgical buttress disposed on the staple cartridge and further comprising a second surgical buttress disposed on the anvil assembly, the first surgical buttress being pre-loaded on the staple cartridge and the second surgical buttress being pre-loaded on the anvil assembly.
 39. The loading unit according to claim 35, wherein the suture is at least partially disposed in the surgical buttress.
 40. A loading unit for use with a surgical stapling apparatus, the loading unit comprising: a tool assembly having a cartridge assembly including a cartridge having a plurality of surgical fasteners therein, and an anvil assembly, at least one of the cartridge assembly and the anvil assembly being movable in relation to the other of the cartridge assembly and anvil assembly, wherein the anvil assembly includes an anvil plate and, wherein each of the anvil plate and the staple cartridge define an elongate longitudinal slot; a surgical buttress disposed on a tissue contacting surface of at least one of the anvil assembly and the staple cartridge, wherein the surgical buttress is secured to the selected one of the anvil assembly and the cartridge assembly by a suture disposed in a retention slot defined in the tissue contacting surface of the selected one of the anvil assembly and the staple cartridge, the suture passing transversely across the surgical buttress; wherein at least one of the anvil assembly and the cartridge assembly includes a constricting, open-ended, side slot configured to grip an end of the suture, and further comprising a release assembly to push the end of the suture out of the retention slot.
 41. The loading unit according to claim 40, further comprising a housing portion removably couplable to an elongated body of the surgical stapling apparatus, the surgical buttress comprising a first surgical buttress disposed on the staple cartridge and further comprising a second surgical buttress disposed on the anvil assembly, the first surgical buttress being pre-loaded on the staple cartridge and the second surgical buttress being pre-loaded on the anvil assembly.
 42. The loading unit according to claim 40, wherein the suture is at least partially disposed in the surgical buttress. 